Glomerulonephritis

Page last reviewed: 13/07/2011

Glomerulonephritis is a condition that affects the kidneys.

It happens when tiny structures inside the kidney, called glomeruli, become diseased. This can be caused by several conditions, but it is often caused by the immune system (the body's natural deference against infection and illness).

Glomerulonephritis may not cause any symptoms and is often diagnosed when blood or urine tests are carried out for another reason. See Glomerulonephritis - symptoms for more information. 

Glomerulonephritis can vary in severity. It can be short-lived (acute) or it can last for a long time (chronic).

Several medicines can be used to treat glomerulonephritis, depending on its cause and how severe it is. See Glomerulonephritis - treatment for more information.

Glomeruli

You have two kidneys in your body. They have a very important function in removing waste products from your blood. These are then passed out of your body in urine.

In each kidney are about 1 million tiny filters called glomeruli. Glomeruli filter waste products from the blood into the urine, while keeping the necessary cells and proteins in the blood. Glomerulonephritis occurs when the glomeruli become affected by one of a wide range of possible diseases.

If the kidneys become affected in this way, they cannot work properly, which causes kidney disease. This can lead to:

  • protein from your blood leaking into your urine
  • red blood cells being detected in your urine
  • waste products and fluid building up in your body

This can cause complications, such as high blood pressure (hypertension). If the kidneys are severely affected, they may no longer work. This is known as kidney failure.

Types of glomerulonephritis

There are several types of glomerulonephritis. However, the condition can be broadly split into two main types: 

  • Primary glomerulonephritis develops on its own and is not related to another condition.
  • Secondary glomerulonephritis develops as a result of another condition.

Conditions that can cause secondary glomerulonephritis include:

These are autoimmune conditions. An autoimmune condition is where your immune system reacts abnormally. Instead of doing its usual job of fighting infection, it attacks your body's healthy tissues.

In most cases, the cause of primary glomerulonephritis is unknown. However, in some cases, a specific cause can be found, such as a reaction to a viral infection or medication. See Glomerulonephritis - causes for more information. 

Antibodies

Antibodies are proteins that are produced by the body to neutralise or destroy disease-carrying organisms and toxins.

Immune system

The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.

Inflammation

Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

Kidneys

Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.

Page last reviewed: 13/07/2011

Glomerulonephritis may not cause any obvious symptoms. If your glomeruli (the tiny filters in your kidneys) have been damaged, small amounts of blood or protein may be present in your urine. This may only become apparent after a sample of your urine has been tested.

In severe cases of glomerulonephritis, more blood may be lost through the glomeruli, causing your urine to turn red. This is known as haematuria. If a large amount of protein is lost through the glomeruli, your urine may also be frothy.

Urinating

Glomerulonephritis rarely causes noticeable changes in your urine. However, see your GP immediately if you suddenly pass much less urine than normal and it is not due to dehydration.

Kidney damage

Damage to the kidneys may not be obvious at first. The symptoms of kidney damage can either come on suddenly or gradually, over weeks or months. There are often no symptoms at all and the condition is picked up when a blood or urine test is carried out for other reasons.

As a result of kidney damage, glomerulonephritis may cause:

  • a puffy face, swollen ankles or breathing problems - this is due to a build-up of fluid in the body (see nephrotic syndrome, below)
  • pale skin - this is due to the lack of red blood cells that can occur with some kidney conditions
  • loss of appetite
  • vomiting

Nephrotic syndrome

If a lot of protein is leaking into your urine, fluid can build up in your body. A build-up of fluid will often develop in your legs and lower back, although it can also sometimes affect your abdomen, face, hands or lungs.

The build-up of fluid occurs because proteins in your blood normally help keep fluid in the blood vessels. However, if a lot of protein leaks into your urine, there will be low protein levels in the blood. This is called nephrotic syndrome.

Other symptoms

Depending on the type of glomerulonephritis you have, you may also develop other symptoms such as:

  • rashes
  • joint pains
  • breathing problems

Kidney pain

It is very rare to get kidney pain with glomerulonephritis. If you have pain on the left or right side of your back, it may have another cause, such as:

  • kidney infection - this usually occurs when a bacterial infection moves from your bladder into one of your kidneys
  • kidney stones - stone-like lumps that can develop in one or both of your kidneys

There are many other causes of back pain that are not due to kidney disease. As back or kidney pain can have several causes, it is important to see your GP for the correct diagnosis.

Kidneys

Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.

Page last reviewed: 13/07/2011

In many cases, the exact cause of glomerulonephritis is unknown. It is thought that the condition is often caused by the immune system, the body's natural defence system against illness and infection.

The immune system

The job of your immune system is to recognise infections early and get rid of them. Your immune system has two main "tools" to use in the fight against infection. These are: 

  • proteins called antibodies 
  • a type of white blood cell called lymphocytes

Both antibodies and lymphocytes circulate in your blood. They stick to substances found on bacteria and viruses, helping get rid of them.

Abnormalities in the immune system  

Many of the body's own chemicals, such as proteins, can be similar to those found on organisms that cause infections, such as bacteria and viruses. Your immune system can mistake these proteins for an infection and attack the cells that carry them. This causes disease.

Glomerulonephritis can be caused by either abnormal antibodies or lymphocytes, or sometimes both. The exact cause of many types of glomerulonephritis is not known. However, in such cases, the cause is known to be related to the immune system working abnormally.

The types of glomerulonephritis that are caused by the immune system reacting against the body's own proteins and other chemicals are:

  • systemic lupus erythematosus - where the immune system attacks many of the body's tissues and organs 
  • anti-glomerular basement membrane disease, also known as Goodpasture's disease - where antibodies attack the membranes of the glomeruli  
  • immunoglobulin A nephropathy, also known as IgA nephropathy and Berger disease - where a build-up of an antibody called immunoglobulin A damages the kidneys 
  • membranous nephropathy (when not caused by medication, cancer or certain infections) - where the membranes of the glomeruli thicken, damaging the kidneys 
  • vasculitis, such as Wegener's granulomatosis - where the immune system attacks the blood vessels in and around the glomeruli    

Although it is not certain, the immune system may also play a role in causing:

  • minimal change disease - where the glomeruli are damaged but the damage can only be seen with a special high-power microscope (this type is more common in children) 
  • focal and segmental glomerulosclerosis - where there is inflammation and scarring of the glomeruli 

Complications of certain infections

It is possible to develop glomerulonephritis as a serious complication of various infections, including:

Inherited glomerulonephritis

Most people who develop glomerulonephritis do not have a family member with the condition. However, certain types of glomerulonephritis can run in families.

If you are diagnosed with a type of glomerulonephritis that runs in families, your doctor can advise you about the chances of someone else in your family being affected. They may recommend screening, which can identify people who may be at increased risk of developing the condition.

Long-term medication use

While certain medicines can affect the function of the kidneys in various ways, they are rarely the cause of glomerulonephritis.

If you are taking medicines that affect your kidney function, your GP or hospital specialist will monitor this with tests (see Glomerulonephritis - diagnosis).

Other causes of glomerulonephritis

Glomerulonephritis can sometimes occur if the glomeruli are damaged by another condition, including:

  • cancer, such as Hodgkin's lymphoma (cancer of the lymphatic system)
  • liver disease
  • sickle cell anaemia - an inherited blood disorder where red blood cells develop abnormally

Antibodies

Antibodies are proteins that are produced by the body to neutralise or destroy disease-carrying organisms and toxins.

Immune system

The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.

Inflammation

Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

Kidneys

Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.

Lymphatic system

The lymphatic system is made up of a network of channels and glands distributed throughout the body. It helps fight infection and drain excess fluid from tissue.

Page last reviewed: 13/07/2011

The symptoms of glomerulonephritis are not always obvious, so it is sometimes only diagnosed after a routine medical check-up or during tests related to:

  • having high blood pressure (hypertension)
  • feeling tired
  • feeling unwell for a long time without an obvious cause 
  • being pregnant

The presence of kidney disease will be picked up in two ways: 

  • during a blood test to measure the kidney's function
  • during a urine test to look for abnormal levels of protein or blood

Blood test

A blood test can be used to measure your creatinine level. Creatinine is a substance produced by your muscles that is present in your blood stream. The kidneys remove creatinine from the blood as part of their usual role.

If your kidneys are not working normally, the creatinine level in your blood will rise, and this can be detected during a blood test.

The creatinine result is converted into what is known as the estimated glomerular filtration rate (eGFR). The eGFR is the best guide to kidney function.

Urine test

Your urine can be tested in two ways: 

  • Your GP or another healthcare professional can dip special strips into a sample of your urine. This is called the dipstick technique, and the strip changes colour if there is any blood or protein in your urine. 
  • A sample of your urine is sent to a laboratory to more accurately measure how much protein it contains or to look for blood cells.

The dipstick technique is generally considered to be better at determining whether there is blood in your urine. The laboratory test is better for measuring protein levels.

If you have glomerulonephritis, these tests may show evidence of too much protein or blood in your urine, or both. You may also have an abnormal eGFR. Putting this information together will allow your GP to decide whether you need to see a specialist for further investigations.

Specialist blood tests

Several specialist blood tests may be carried out to look for causes of glomerulonephritis. These include:

  • tests to look for systemic lupus erythematosus, such as an anti-nuclear antibody test - see Systemic lupus erythematosus - diagnosis for more information 
  • the anti-neutrophil cytoplasmic antibody blood test - used to diagnose vasculitis (a condition that affects the small blood vessels of various organs in the body)
  • the anti-glomerular basement membrane blood test - used to diagnose Goodpasture's disease (when antibodies attack the membranes of the glomeruli) 

Kidney ultrasound

If your kidney problem needs to be investigated further, it is likely that you will need to have a kidney ultrasound scan.

An ultrasound scan uses high-frequency sound waves to allow the specialist to look at images of your kidneys. The specialist will be able to check the size of your kidneys, make sure there are no blockages and look for anything else that might explain why they are not working as they should.

If you need a kidney biopsy (see below), you will need a kidney ultrasound scan first.  

Kidney biopsy

If glomerulonephritis is suspected, a procedure to remove a small sample of kidney tissue (a biopsy) may be recommended. See the Health A-Z topic about Biopsies for more information.

A kidney biopsy is usually carried out using local anaesthetic to numb the area. An ultrasound machine will be used to locate your kidneys and a small needle will be used to take a sample. The test carries a small risk of bleeding so you will need to remain in hospital for a while on the day of the procedure, or sometimes overnight.

After the procedure, the tissue sample will be examined under a microscope in a laboratory to find out how serious the condition is and to determine the most appropriate type of treatment.

Antibodies

Antibodies are proteins that are produced by the body to neutralise or destroy disease-carrying organisms and toxins.

Immune system

The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.

Kidneys

Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.

Page last reviewed: 13/07/2011

If you are diagnosed with glomerulonephritis, the healthcare professional treating you will focus on treating the cause of the condition as well as the symptoms.

Dietary changes

You may be advised to:

  • drink less fluids 
  • reduce your intake of food or drinks that contain a high amount of sodium chloride (salt) or potassium

Sodium chloride and potassium in your blood have several different roles, such as helping regulate the amount of water in your body. 

As glomerulonephritis can lead to a build-up of fluid, monitoring your intake of fluid and these minerals will help control the amount of fluid in your body.

Your diet will also need to be carefully controlled. Your GP or dietitian (a specialist in nutrition) will give you advice about eating protein and controlling your intake of potassium, salt and, sometimes, phosphate.

Phosphate is a mineral that, with calcium, makes up most of your bones. You get phosphate through your diet, mainly from dairy foods. Your kidneys usually filter out excess phosphate. If phosphate levels rise too much, it can upset the normal calcium balance of your body. This can lead to thinning of your bones and furring of your arteries.

Your blood will be regularly reviewed to ensure that it contains the right levels of potassium and sodium chloride, and that the amount of fluid in your diet is correct.

Medication

Glomerulonephritis is sometimes treated with medicines that suppress or control your immune system (the body's natural defence against infection and illness). These types of medicines are known as immunosuppressant medicines.

It is thought that your immune system plays a part in causing glomerulonephritis (see Glomerulonephritis - causes). Therefore, suppressing your immune system can be an effective way to treat the condition. However, suppressing your immune system increases your risk of infections. Because of this, treatment with immunosuppressant medicines will be kept at the minimum level needed to treat your condition while lessening the risk of infections. 

Other types of medicines may also be recommended to treat the underlying cause of glomerulonephritis, plus any other response that your body has to the condition.

Angiotensin-converting enzyme (ACE) inhibitors

Angiotensin-converting enzyme (ACE) inhibitors are a type of medicine that can be used to decrease the amount of protein in your urine. Reducing the amount of protein in your urine improves the outlook for the kidneys, regardless of the cause of the protein leak. ACE inhibitors are also widely used to treat high blood pressure in people with or without kidney disease.

Corticosteroids

Corticosteroids are medicines that contain steroids, a type of hormone. Hormones are powerful chemicals that have a wide range of effects on the body.

Corticosteroids are used to reduce inflammation (swelling) and suppress your immune system. Prednisolone is the most common corticosteroid that you might be prescribed.

See the Health A-Z topic about Corticosteroids for more information about this type of medication.

Cyclophosphamide

Cyclophosphamide is used in very high doses to treat some cancers, but it is also an established treatment, in much lower doses, for glomerulonephritis.

Other medicines

Other medicines to help control your immune system include: 

  • rituximab - an antibody medicine that attacks the white blood cells that can produce antibodies
  • mycophenolate mofetil - an immunosuppressant
  • ciclosporin - an immunosuppressant
  • tacrolimus - an immunosuppressant

Maintenance therapy

Once your kidneys have started to recover, your dose of corticosteroid medicine will usually be lowered. You may continue to take other medicines, or you may change to something that is not as strong. For example, you may change to azathioprine. 

Plasma exchange

Plasma is a clear, yellowish fluid that is part of the blood. It contains proteins, such as the antibodies that cause your kidneys to become inflamed. Plasma exchange is a procedure that removes some of the plasma from your blood.

During plasma exchange, you are connected to a machine that removes some of your blood. The plasma is separated from the blood cells and removed. The blood cells are then put back into your body. The removed fluid is replaced, either with regular fluids or with the plasma from healthy blood donors.

Plasma exchange may be used if your condition is particularly severe. Evidence suggests it may reduce the risk of end-stage kidney failure, where the kidneys have permanently failed.

See the Health A-Z topic about Plasma products - how they are used for more information about plasma exchange.

Treating high blood pressure

Glomerulonephritis can lead to high blood pressure (hypertension), which can cause further kidney damage and other health problems.

Your blood pressure will be carefully monitored by the healthcare professional who is treating you, and you may need to take medicines, such as ACE inhibitors. Often, people who have high blood pressure and kidney disease need to take several medicines to control their blood pressure.

See the Health A-Z topic about High blood pressure for more information.

Treating chronic kidney disease or kidney failure

In severe cases, if you have long-term kidney disease or your kidneys no longer work, you may need:

  • kidney dialysis - where a machine is used to do the kidney's job of removing waste products from your body 
  • kidney transplant - where a healthy kidney from a donor is surgically implanted

 

Antibodies

Antibodies are proteins that are produced by the body to neutralise or destroy disease-carrying organisms and toxins.

Immune system

The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.

Inflammation

Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.

Kidneys

Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.

White blood cells

White blood cells are the part of blood that fights infection and disease.

Page last reviewed: 13/07/2011

The possible complications of glomerulonephritis vary according to the type and severity of the condition. Complications of glomerulonephritis can include:

  • high blood pressure (hypertension)
  • problems with other internal organs as well as the kidneys
  • kidney failure, in rare cases 

High blood pressure

High blood pressure is a common complication of glomerulonephritis. This is because your kidneys help regulate your blood pressure.

Many people with glomerulonephritis are prescribed medication to help lower their blood pressure. If this type of medication is recommended for you, it is important to take it as prescribed to protect your kidneys from further damage. It will also help reduce your risk of developing other conditions caused by high blood pressure.

If left untreated or not fully treated, long-term high blood pressure increases your risk of developing: 

  • heart disease 
  • a stroke 
  • problems with the circulation to your legs
  • further worsening of your kidney function

See the Health A-Z topic about High blood pressure for more information.

Effects on other internal organs

In most people, glomerulonephritis only affects the kidneys. However, in some types of glomerulonephritis, the immune system (the body's natural defence against infection and illness) can also affect other parts of your body. These conditions include:

  • systemic lupus erythematosus - when the immune system attacks many of the body's tissues and organs 
  • vasculitis - a condition that affects the small blood vessels of various organs in the body
  • Henoch-Schonlein purpura - a condition caused by an abnormal immune system response that causes a range of symptoms 

The effects can range from a spotty red rash over your legs to painful swollen joints or adverse effects on your lungs and liver.

Discuss any symptoms you have with your GP or kidney specialist to determine whether they could be related to glomerulonephritis.

Kidney disease or kidney failure

Kidney disease and kidney failure are rare, but glomerulonephritis can damage the kidneys so that they fail completely. Glomerulonephritis causes around a quarter of long-term kidney failure cases.

See the Health A-Z topic about Chronic kidney disease for more information.

Immune system

The immune system is the body's defence system, which helps protect it from disease, bacteria and viruses.

Kidneys

Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.

 

Content provided by NHS Choices www.nhs.uk and adapted for Ireland by the Health A-Z.

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